""" ILeo - Leo plugin for IPython

   
"""
import IPython.ipapi
import IPython.genutils
import IPython.generics
from IPython.hooks import CommandChainDispatcher
import re
import UserDict
from IPython.ipapi import TryNext 
import IPython.macro
import IPython.Shell

def init_ipython(ipy):
    """ This will be run by _ip.load('ipy_leo') 
    
    Leo still needs to run update_commander() after this.
    
    """
    global ip
    ip = ipy
    IPython.Shell.hijack_tk()
    ip.set_hook('complete_command', mb_completer, str_key = '%mb')
    ip.expose_magic('mb',mb_f)
    ip.expose_magic('lee',lee_f)
    ip.expose_magic('leoref',leoref_f)
    expose_ileo_push(push_cl_node,100)
    # this should be the LAST one that will be executed, and it will never raise TryNext
    expose_ileo_push(push_ipython_script, 1000)
    expose_ileo_push(push_plain_python, 100)
    expose_ileo_push(push_ev_node, 100)
    global wb
    wb = LeoWorkbook()
    ip.user_ns['wb'] = wb 
    
    show_welcome()


def update_commander(new_leox):
    """ Set the Leo commander to use
    
    This will be run every time Leo does ipython-launch; basically,
    when the user switches the document he is focusing on, he should do
    ipython-launch to tell ILeo what document the commands apply to.
    
    """
    
    global c,g
    c,g = new_leox.c, new_leox.g
    print "Set Leo Commander:",c.frame.getTitle()
    
    # will probably be overwritten by user, but handy for experimentation early on
    ip.user_ns['c'] = c
    ip.user_ns['g'] = g
    ip.user_ns['_leo'] = new_leox
    
    new_leox.push = push_position_from_leo
    run_leo_startup_node()

from IPython.external.simplegeneric import generic 
import pprint

def es(s):    
    g.es(s, tabName = 'IPython')
    pass

@generic
def format_for_leo(obj):
    """ Convert obj to string representiation (for editing in Leo)"""
    return pprint.pformat(obj)

@format_for_leo.when_type(list)
def format_list(obj):
    return "\n".join(str(s) for s in obj)
  

attribute_re = re.compile('^[a-zA-Z_][a-zA-Z0-9_]*$')
def valid_attribute(s):
    return attribute_re.match(s)    

_rootnode = None
def rootnode():
    """ Get ileo root node (@ipy-root) 
    
    if node has become invalid or has not been set, return None
    
    Note that the root is the *first* @ipy-root item found    
    """
    global _rootnode
    if _rootnode is None:
        return None
    if c.positionExists(_rootnode.p):
        return _rootnode
    _rootnode = None
    return None  

def all_cells():
    global _rootnode
    d = {}
    r = rootnode() 
    if r is not None:
        nodes = r.p.children_iter()
    else:
        nodes = c.allNodes_iter()

    for p in nodes:
        h = p.headString()
        if h.strip() == '@ipy-root':
            # update root node (found it for the first time)
            _rootnode = LeoNode(p)            
            # the next recursive call will use the children of new root
            return all_cells()
        
        if h.startswith('@a '):
            d[h.lstrip('@a ').strip()] = p.parent().copy()
        elif not valid_attribute(h):
            continue 
        d[h] = p.copy()
    return d    

def eval_node(n):
    body = n.b    
    if not body.startswith('@cl'):
        # plain python repr node, just eval it
        return ip.ev(n.b)
    # @cl nodes deserve special treatment - first eval the first line (minus cl), then use it to call the rest of body
    first, rest = body.split('\n',1)
    tup = first.split(None, 1)
    # @cl alone SPECIAL USE-> dump var to user_ns
    if len(tup) == 1:
        val = ip.ev(rest)
        ip.user_ns[n.h] = val
        es("%s = %s" % (n.h, repr(val)[:20]  )) 
        return val

    cl, hd = tup 

    xformer = ip.ev(hd.strip())
    es('Transform w/ %s' % repr(xformer))
    return xformer(rest, n)

class LeoNode(object, UserDict.DictMixin):
    """ Node in Leo outline
    
    Most important attributes (getters/setters available:
     .v     - evaluate node, can also be alligned 
     .b, .h - body string, headline string
     .l     - value as string list
    
    Also supports iteration, 
    
    setitem / getitem (indexing):  
     wb.foo['key'] = 12
     assert wb.foo['key'].v == 12
    
    Note the asymmetry on setitem and getitem! Also other
    dict methods are available. 
    
    .ipush() - run push-to-ipython

    Minibuffer command access (tab completion works):
    
     mb save-to-file
    
    """
    def __init__(self,p):
        self.p = p.copy()

    def __str__(self):
        return "<LeoNode %s>" % str(self.p)
    
    __repr__ = __str__
    
    def __get_h(self): return self.p.headString()
    def __set_h(self,val):
        print "set head",val
        c.beginUpdate() 
        try:
            c.setHeadString(self.p,val)
        finally:
            c.endUpdate()
        
    h = property( __get_h, __set_h, doc = "Node headline string")  

    def __get_b(self): return self.p.bodyString()
    def __set_b(self,val):
        print "set body",val
        c.beginUpdate()
        try: 
            c.setBodyString(self.p, val)
        finally:
            c.endUpdate()
    
    b = property(__get_b, __set_b, doc = "Nody body string")
    
    def __set_val(self, val):        
        self.b = format_for_leo(val)
        
    v = property(lambda self: eval_node(self), __set_val, doc = "Node evaluated value")
    
    def __set_l(self,val):
        self.b = '\n'.join(val )
    l = property(lambda self : IPython.genutils.SList(self.b.splitlines()), 
                 __set_l, doc = "Node value as string list")
    
    def __iter__(self):
        """ Iterate through nodes direct children """
        
        return (LeoNode(p) for p in self.p.children_iter())

    def __children(self):
        d = {}
        for child in self:
            head = child.h
            tup = head.split(None,1)
            if len(tup) > 1 and tup[0] == '@k':
                d[tup[1]] = child
                continue
            
            if not valid_attribute(head):
                d[head] = child
                continue
        return d
    def keys(self):
        d = self.__children()
        return d.keys()
    def __getitem__(self, key):
        """ wb.foo['Some stuff'] Return a child node with headline 'Some stuff'
        
        If key is a valid python name (e.g. 'foo'), look for headline '@k foo' as well
        """  
        key = str(key)
        d = self.__children()
        return d[key]
    def __setitem__(self, key, val):
        """ You can do wb.foo['My Stuff'] = 12 to create children 
        
        This will create 'My Stuff' as a child of foo (if it does not exist), and 
        do .v = 12 assignment.
        
        Exception:
        
        wb.foo['bar'] = 12
        
        will create a child with headline '@k bar', because bar is a valid python name
        and we don't want to crowd the WorkBook namespace with (possibly numerous) entries
        """
        key = str(key)
        d = self.__children()
        if key in d:
            d[key].v = val
            return
        
        if not valid_attribute(key):
            head = key
        else:
            head = '@k ' + key
        p = c.createLastChildNode(self.p, head, '')
        LeoNode(p).v = val
        
    def ipush(self):
        """ Does push-to-ipython on the node """
        push_from_leo(self)
        
    def go(self):
        """ Set node as current node (to quickly see it in Outline) """
        c.beginUpdate()
        try:
            c.setCurrentPosition(self.p)
        finally:
            c.endUpdate()  
        
    def script(self):
        """ Method to get the 'tangled' contents of the node
        
        (parse @others, << section >> references etc.)
        """
        return g.getScript(c,self.p,useSelectedText=False,useSentinels=False)
    
    def __get_uA(self):
        p = self.p
        # Create the uA if necessary.
        if not hasattr(p.v.t,'unknownAttributes'):
            p.v.t.unknownAttributes = {}        
        
        d = p.v.t.unknownAttributes.setdefault('ipython', {})
        return d        
    
    uA = property(__get_uA, doc = "Access persistent unknownAttributes of node")
        

class LeoWorkbook:
    """ class for 'advanced' node access 
    
    Has attributes for all "discoverable" nodes. Node is discoverable if it 
    either
    
    - has a valid python name (Foo, bar_12)
    - is a parent of an anchor node (if it has a child '@a foo', it is visible as foo)
    
    """
    def __getattr__(self, key):
        if key.startswith('_') or key == 'trait_names' or not valid_attribute(key):
            raise AttributeError
        cells = all_cells()
        p = cells.get(key, None)
        if p is None:
            return add_var(key)

        return LeoNode(p)

    def __str__(self):
        return "<LeoWorkbook>"
    def __setattr__(self,key, val):
        raise AttributeError("Direct assignment to workbook denied, try wb.%s.v = %s" % (key,val))
        
    __repr__ = __str__
    
    def __iter__(self):
        """ Iterate all (even non-exposed) nodes """
        cells = all_cells()
        return (LeoNode(p) for p in c.allNodes_iter())
    
    current = property(lambda self: LeoNode(c.currentPosition()), doc = "Currently selected node")
    
    def match_h(self, regex):
        cmp = re.compile(regex)
        for node in self:
            if re.match(cmp, node.h, re.IGNORECASE):
                yield node
        return

@IPython.generics.complete_object.when_type(LeoWorkbook)
def workbook_complete(obj, prev):
    return all_cells().keys() + [s for s in prev if not s.startswith('_')]
    

def add_var(varname):
    c.beginUpdate()
    r = rootnode()
    try:
        if r is None:
            p2 = g.findNodeAnywhere(c,varname)
        else:
            p2 = g.findNodeInChildren(c, r.p, varname)
        if p2:
            return LeoNode(p2)

        if r is not None:
            p2 = r.p.insertAsLastChild()
        
        else:
            p2 =  c.currentPosition().insertAfter()
        
        c.setHeadString(p2,varname)
        return LeoNode(p2)
    finally:
        c.endUpdate()

def add_file(self,fname):
    p2 = c.currentPosition().insertAfter()

push_from_leo = CommandChainDispatcher()

def expose_ileo_push(f, prio = 0):
    push_from_leo.add(f, prio)

def push_ipython_script(node):
    """ Execute the node body in IPython, as if it was entered in interactive prompt """
    c.beginUpdate()
    try:
        ohist = ip.IP.output_hist 
        hstart = len(ip.IP.input_hist)
        script = node.script()
                
        ip.user_ns['_p'] = node
        ip.runlines(script)
        ip.user_ns.pop('_p',None)
        
        has_output = False
        for idx in range(hstart,len(ip.IP.input_hist)):
            val = ohist.get(idx,None)
            if val is None:
                continue
            has_output = True
            inp = ip.IP.input_hist[idx]
            if inp.strip():
                es('In: %s' % (inp[:40], ))
                
            es('<%d> %s' % (idx, pprint.pformat(ohist[idx],width = 40)))
        
        if not has_output:
            es('ipy run: %s (%d LL)' %( node.h,len(script)))
    finally:
        c.endUpdate()

    
def eval_body(body):
    try:
        val = ip.ev(body)
    except:
        # just use stringlist if it's not completely legal python expression
        val = IPython.genutils.SList(body.splitlines())
    return val 
    
def push_plain_python(node):
    if not node.h.endswith('P'):
        raise TryNext
    script = node.script()
    lines = script.count('\n')
    try:
        exec script in ip.user_ns
    except:
        print " -- Exception in script:\n"+script + "\n --"
        raise
    es('ipy plain: %s (%d LL)' % (node.h,lines))
    

def push_cl_node(node):
    """ If node starts with @cl, eval it
    
    The result is put as last child of @ipy-results node, if it exists
    """
    if not node.b.startswith('@cl'):
        raise TryNext
        
    p2 = g.findNodeAnywhere(c,'@ipy-results')
    val = node.v
    if p2:
        es("=> @ipy-results")
        LeoNode(p2).v = val
    es(val)

def push_ev_node(node):
    """ If headline starts with @ev, eval it and put result in body """
    if not node.h.startswith('@ev '):
        raise TryNext
    expr = node.h.lstrip('@ev ')
    es('ipy eval ' + expr)
    res = ip.ev(expr)
    node.v = res
    
    
def push_position_from_leo(p):
    push_from_leo(LeoNode(p))         

@generic
def edit_object_in_leo(obj, varname):
    """ Make it @cl node so it can be pushed back directly by alt+I """
    node = add_var(varname)
    formatted = format_for_leo(obj)
    if not formatted.startswith('@cl'):
        formatted = '@cl\n' + formatted
    node.b = formatted 
    node.go()
    
@edit_object_in_leo.when_type(IPython.macro.Macro)
def edit_macro(obj,varname):
    bod = '_ip.defmacro("""\\\n' + obj.value + '""")'
    node = add_var('Macro_' + varname)
    node.b = bod
    node.go()

def get_history(hstart = 0):
    res = []
    ohist = ip.IP.output_hist 

    for idx in range(hstart, len(ip.IP.input_hist)):
        val = ohist.get(idx,None)
        has_output = True
        inp = ip.IP.input_hist_raw[idx]
        if inp.strip():
            res.append('In [%d]: %s' % (idx, inp))
        if val:
            res.append(pprint.pformat(val))
            res.append('\n')    
    return ''.join(res)
    
    
def lee_f(self,s):
    """ Open file(s)/objects in Leo
    
    - %lee hist -> open full session history in leo
    - Takes an object. l = [1,2,"hello"]; %lee l. Alt+I in leo pushes the object back
    - Takes an mglob pattern, e.g. '%lee *.cpp' or %lee 'rec:*.cpp'
    - Takes input history indices:  %lee 4 6-8 10 12-47
    """
    import os
        
    c.beginUpdate()
    try:
        if s == 'hist':
            wb.ipython_history.b = get_history()
            wb.ipython_history.go()
            return
        
            
        if s and s[0].isdigit():
            # numbers; push input slices to leo
            lines = self.extract_input_slices(s.strip().split(), True)
            v = add_var('stored_ipython_input')
            v.b = '\n'.join(lines)
            return
            
        
        # try editing the object directly
        obj = ip.user_ns.get(s, None)
        if obj is not None:
            edit_object_in_leo(obj,s)
            return
     
        
        # if it's not object, it's a file name / mglob pattern
        from IPython.external import mglob
        
        files = (os.path.abspath(f) for f in mglob.expand(s))
        for fname in files:
            p = g.findNodeAnywhere(c,'@auto ' + fname)
            if not p:
                p = c.currentPosition().insertAfter()
            
            p.setHeadString('@auto ' + fname)
            if os.path.isfile(fname):
                c.setBodyString(p,open(fname).read())
            c.selectPosition(p)
        print "Editing file(s), press ctrl+shift+w in Leo to write @auto nodes"
    finally:
        c.endUpdate()



def leoref_f(self,s):
    """ Quick reference for ILeo """
    import textwrap
    print textwrap.dedent("""\
    %leoe file/object - open file / object in leo
    wb.foo.v  - eval node foo (i.e. headstring is 'foo' or '@ipy foo')
    wb.foo.v = 12 - assign to body of node foo
    wb.foo.b - read or write the body of node foo
    wb.foo.l - body of node foo as string list
    
    for el in wb.foo:
      print el.v
       
    """
    )



def mb_f(self, arg):
    """ Execute leo minibuffer commands 
    
    Example:
     mb save-to-file
    """
    c.executeMinibufferCommand(arg)

def mb_completer(self,event):
    """ Custom completer for minibuffer """
    cmd_param = event.line.split()
    if event.line.endswith(' '):
        cmd_param.append('')
    if len(cmd_param) > 2:
        return ip.IP.Completer.file_matches(event.symbol)
    cmds = c.commandsDict.keys()
    cmds.sort()
    return cmds

def show_welcome():
    print "------------------"
    print "Welcome to Leo-enabled IPython session!"
    print "Try %leoref for quick reference."
    import IPython.platutils
    IPython.platutils.set_term_title('ILeo')
    IPython.platutils.freeze_term_title()

def run_leo_startup_node():
    p = g.findNodeAnywhere(c,'@ipy-startup')
    if p:
        print "Running @ipy-startup nodes"
        for n in LeoNode(p):
            push_from_leo(n)
            

